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UPDATE: July 26

On July 22nd, a Southwest Airlines 737 suffered a collapse of its nose gear upon landing at La Guardia airport. Ten people were injured.

Investigators are now saying that the jet’s gear may have failed not because of a malfunction, but because the pilots managed to land nose-first, causing it to bend backwards, seriously damaging the gear assembly and avionics bay. According to reports, the jet hit the runway at an angle of about three degrees nose-down. That might not sound like much, but even a steep descent is typically made at no more than five degrees or so. And any amount of nose-down pitch on touchdown is a problem. A correct landing attitude, while it varies with wind and other factors, is almost always a few degrees nose-up.

Why is it bad for a plane to land on its nose gear? Well, why is it bad for a bird to land on its face? And if indeed this is what happened at LGA, the question shifts to why and how the pilots found themselves in such an unusual predicament.

It remains true, however, that although landing gear issues are frightening to many people, seldom if ever are they going to result in a crash. Some are more serious than others — for example, the belly landing of a Boeing 767 in Poland two years ago, which I wrote about here — but in general they’re pretty innocuous, and from a pilot’s perspective they are way, way down the list of nightmare scenarios.

This is why, when the Southwest story first broke, I tried to ignore it, hoping it would go away. I find gear problems to be, well, a little boring and not worth a whole lot of attention. But the press was in a bit of a frenzy (so it goes when there’s an airplane accident, no matter how minor, in the heart of the world’s hungriest media market) and I felt obliged to chime in.

And once you’re done with Slate, CLICK OVER TO FLYERTALK for my fond remembrance of LGA’s quirky old control tower.

It may not have been state-of-the-art, but La Guardia’s old tower, whimsically bejeweled with a top-to-bottom series of portholes, gave a welcoming, almost roguish flourish to an otherwise joyless vista of seawater and concrete. It lent a friendly touch to an airport that, in too many respects, is anything but friendly. It was, almost literally, an exclamation point. It said: La Guardia!

The problem with “objects” flying around is that when you decelerate at say 20G (200m/s^2) for 0.1 seconds, you’ll be fine. People can tolerate that for short periods of time. (It’s close to the limit. Put 100 people through that and most will be OK, but a few might sustain injuries)

But if the “object” happens to be “not attached” to the decelerating plane, it will be moving at about 70km/h or 45 mph by the time it might hit your head. That might well be fatal.

What I found interesting in all the reports were all the quotes about phones, books, drinks, etc., all flying about the cabin when the nose hit. I’ve been reminding people that’s why the attendants tell you to put all that crap away prior to landing. Alas.

It damaged the avionics bay because the nosegear folded aft rather than retracting forward into the nosegear well, as a partially deployed nosewheel almost certainly would have if the nose had been lowered after main-gear touchdown.

Other key point that the preliminary investigation seems to have come up with: aircraft attitude at touchdown was three degrees nosedown. Three degrees might not sound like much, but it’s the angle at which a glideslope meets the runway.

According to the report, the airplane had a Center hydraulic system failure [leak] soon after takeoff from Newark, but the crew decided to continue across the Atlantic to Warsaw

Patrick, you’re a 767 pilot. Would you have dumped fuel and returned to Newark or tried to save your company the cost of the delay – probable cancellation – by crossing the Atlantic to get home on the remaining hydraulics. Under ETOPS rules

The crew pulled a vital circuit breaker after takeoff; it was still pulled after the belly landing at Warsaw. Patrick, should the breaker have been reset?

The pilot did a great job getting everyone down safely. Is he still working at LOT? Should he be?

Patrick, you write they lost directional control, as if that is a seldomly seen side-effect of having the nose gear collapse.

I’d say it is a guaranteed side-effect of losing the nose wheel. You’ll have rudder-control until you slow down that aerodynamic effects become small. Then you lose directional control. Now, occasionally the plane will go straight and stay on the landing strip. But /that/ is just luck.

unless I’m mistaken, the stubby base of the old tower is still there — since it was built into one of terminal B’s concourses.

Also, I’m surprised to hear no mention of the soon to be demolished Pan Am Worldport at JFK. It’s now being ripped apart to make way for more aircraft parking space. Delta had taken over that terminal and Terminal 2 (a less distinctive early-jet-age terminal). T2 is also slated for demolition in a few years and Delta will be T4 only.

The TWA Flight Center (T5) got saved, but I hear the inside has been hollowed out…

We often refer to jet fuel colloquially as “gas,” though certainly never as gasoline. Though you’re absolutely right, it’s a little like pointing out to Jeff Gordon that it wasn’t his “motor” that blew on the fiftieth lap, it was his engine, since motors are electric.

In an article I read a few years back on the ATC system in the greater New York area, apparently the old tower was simply worn out. Roof leaks, flaky electrical, malfunctioning climate control, etc. But yeah, it would have been nice if the new tower had some sort of interesting design. I do think it’s better than the tri-pyloned previous generation generic tower design.

FYI, the article depicted the morale and esprit de corps in the LGA tower as much better (despite the lousy facilities) than the NYC-area TRACON in Westbury, which was described as being mired in an unending war of management and labor acrimony.

Back in the old days, buildings like the tower were built by architects with talent and were built to last. They don’t wear out, ever; they get old and need renovation. It’s not unusual for the cost of renovation to equal the cost of replacing and people without an appreciation for beauty choose to replace. It takes far less skill to replace. Government agencies like the FAA probably wouldn’t even consider renovation. It helps to get old buildings on the Historic Register; then grants are available. For anyone who thinks a building from the good old days can wear out, one example should correct that notion forever – Fenway. For anyone who thinks a beautiful old building has to be replaced with ugly new one, just take in an Orioles game at Camden Yards.

I read somewhere that the old tower obscured the view of either taxiways or runway intersections, so had to be torn down. A real shame. Even if they needed a new tower, it would’ve been great to keep the old one. As a Queens native, it feels like my old childhood house was renovated into something boring and ugly.

It’s interesting that in the case of the Gimli Glider, the nosewheel also collapsed, which in fact contributed greatly to the successful landing. The airplane landed on a closed runway that was being used for a sports-car gymkhana, and the drag of the wheelless nose helped to stop the airplane quickly enough to avoid hitting anyone on the ground.

The Gimli Glider certainly never “lost all controls,” by the way. It lost all engine power. It in fact had so much control that the captain slipped it like a sailplane when he found that he was a little too high on final. A sporty maneuver in a big Boeing.

The nosewheel of the Gimli Glider didn’t “collapse” so much as it never fully deployed. On the 767, as on many airliners, the nose gear is hinged to fold backward (with the airflow, from the perspective of a flying airplane) into the gear well, and drag must be overcome to get the gear fully down and locked. When the engines flamed out due to fuel starvation, the auxiliary ram air turbine was unable to provide sufficient hydraulic pressure to fully deploy the nose gear.

Your comment would be informative and valuable if it weren’t completely false.

Commercial aircraft nose gear retract forward and extend aft for EXACTLY this reason. The retraction is hydraulically powered and can overcome the air drag. Extension is aided by gravity and drag so that if the hydraulics have failed, the gear will/should extend to the fully down and locked position.

There’s a fundamental difference between a properly deployed gear which collapses due to external forces (As in Gimli) and a gear that fails to deploy or does so improperly. His “explanation” suggests a design flaw with the aircraft which prevented proper deployment, and he went through multiple error-filled sentences to belabor his point.

Also, I failed to mention that the forward motion of the aircraft would tend to push the nose gear farther towards the deployed position, further working to prevent collapse.

Though at this point, it appears that this whole discussion is irrelevant regarding the WN incident at hand, as the NTSB has identified that the aircraft landed at approximately 3* nose down.

It didn’t run out of “gas”. It was a turbine powered aircraft, not an Otto cycle, piston-engined craft. The usual fuel for aircraft turbines is Jet A1 (essentially kerosene). It’s most definitely not gasoline.

The Gimli Glider, a 767 that was retired from the Air Canada fleet only a few years ago, was the victim of confusion over gallons and litres, a bum fuel gauge (known to the crew I believe), a lackadaisical fueller, and the failure to manually check the fuel — all of which left them suddenly powerless over far western Ontario on a flight from Ottawa to Edmonton.

At first they thought they might make Winnipeg, but when it became evident this was impossible, they spotted the decommissoned airbase at Gimli between the clouds. (The first officer had trained there I believe). They were too high for a straight-in approach but didn’t dare trying the other way. So the captain — an experienced glider pilot — side-slipped the 767 to lose height (a previously untried manoeuvre on that aircraft).

The go-kart people using the runway must have popped a garter or two seeing this huge thing looming down on them, but no-one was hurt in the nose-down roll-out.

The pilots were heroes, then stopped looking quite so heroic as the investigation progressed.

Last night the CBC did a story on the 30th anniversary of the “Gimli Glider”– an Air Canada plane that lost all controls and had to be landed at an old military airstrip without a tower, emergency personnel, or even assurances that the runway would be empty. Pretty impressive stuff.No fire, no breaking apart, and no injuries.